Preemies Sustain Elevated Heart Risks in Later Life

There was an association between preterm birth and new-onset heart failure (HF) that persisted as children aged into adulthood, a Swedish cohort study of more than 4 million people showed.

Compared with full-term birth (gestational age 39-41 weeks), preterm birth (less than 37 weeks) was linked with an increased risk of HF diagnosis at:

  • Age <1 year: adjusted HR (aHR) 4.49, 95% CI 3.86-5.22
  • Age 1-17: aHR 3.42, 95% CI 2.75-4.27
  • Age 18-43: aHR 1.42, 95% CI 1.19-1.71

“These risks declined with longer follow-up but remained significantly elevated into early adulthood and mid-adulthood. However, the absolute risks of HF associated with preterm birth were overall low across these ages,” reported researchers led by Casey Crump, MD, PhD, of Icahn School of Medicine at Mount Sinai in New York City, in their study online in JAMA Pediatrics.

Co-sibling analyses suggested that mechanisms connecting preterm birth with HF differed for early-life HF vs adult-onset HF, with the latter largely explained by shared genetic or early-life environmental factors in families.

“Our findings suggest that individuals born preterm may need long-term clinical follow-up into adulthood for preventive evaluation and monitoring, even among those without known cardiac abnormalities,” Crump’s group said.

Clinicians across several disciplines need to pay attention, according to an accompanying editorial by Mandy Belfort, MD, MPH, of Brigham and Women’s Hospital and Harvard Medical School, and Suzanne Sacks, MD, MS, of Vanderbilt University School of Medicine in Nashville.

“For high-risk infant follow-up programs, this study in combination with mounting evidence about other cardiometabolic risks faced by infants born preterm suggests a consideration of expanding the focus of services beyond neurodevelopment to include surveillance for other health risks, including cardiovascular health,” Belfort and Sacks wrote.

“Clinicians who provide primary care for children and adults who were born preterm should carefully screen for hypertension and diabetes as well as for exercise intolerance, which could point to underlying cardiac dysfunction, particularly in the absence of substantial lung disease. For cardiologists who care for young adults presenting with newly diagnosed HF, a careful birth history could shed light on an otherwise idiopathic diagnosis,” the editorialists added.

“Overall, the findings by Crump et al shed new light on HF as a long-term consequence of preterm birth and highlight opportunities for clinicians caring for preterm-born infants across the lifespan to understand their unique health risks and tailor their preventive and disease-specific care accordingly,” Belfort and Sacks concluded.

The population-based study was based on live births from 1973 to 2014 in Sweden (n=4,193,069). Gestational age at birth was collected from nationwide birth records. At the time of analysis, the cohort had a maximum age of 43 and a median age of 22.5.

Links between preterm birth and HF persisted after excluding people with structural congenital cardiac anomalies, suggesting that congenital heart disease is not a major contributing factor.

Investigators also stratified the risk of HF in adulthood according to gestational age at birth:

  • Extremely preterm birth (22-27 weeks): aHR 4.72, 95% CI 2.11-10.52
  • Moderately preterm births (28-33 weeks): aHR 1.93, 95% CI 1.37-2.71
  • Late preterm births (34-36 weeks): aHR 1.24, 95% CI 1.00-1.54
  • Early-term births (37-38 weeks): aHR 1.09, 95% CI 0.97-1.24

Crump and co-authors said the study was limited by the lack of data on echocardiographic information and lifestyle factors such as physical activity, diet, obesity, smoking, and alcohol use.

Also, noted Belfort and Sacks, “more specific information about the type of HF is needed because right-sided and left-sided HF, as well as systolic and diastolic HF, have distinct causes and treatments. Another relevant question is whether the type of HF varies by age of presentation.”

Furthermore, the editorialists added, it remains to be seen “whether screening for early, asymptomatic signs of altered cardiac structure or reduced function on imaging at [neonatal intensive care unit] discharge can predict the development of clinically significant HF over time and therefore form the basis for monitoring strategies embedded within high-risk infant follow-up and/or primary or specialty care.”